The Sysadmin’s Daily Grind: Tor

SECRET SURFING

Some people don’t mind leaving traces of their IP address wherever they go, others prefer to use a tool like The Onion Router.

The Onion Router (Tor) [1] runs as a Socks 4 proxy and mangles incoming connections through a network of distributed, independent servers, thus removing any traces of the original data packets. The Onion is similar to Java Anonymous Proxy (JAP), a tool that supports anonymous web surfing. Your ex won’t be able to evaluate the IP address of a blog entry to find out who added those unflattering comments about her. The IP address will be that of the last server in the Onion routing chain. I downloaded Tor from [2], which has a collection of ready-made packages for a variety of Linux distributions, BSD derivates, MacOS, and Windows. I decided to build from scratch using the current tarballs, a quick process. I had to install the OpenSSL and Libevent libraries on my machine, but then it was standard procedure: ./configure && make && make install. As I did not specify any preferences for the target directory, the binaries ended up in /usr/local/bin, and a sample configuration file was placed in /usr/local/etc/tor/.

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